A survey of traditional Iranian food products for contamination with toxigenic Clostridium botulinum

Abstract

This study aimed to determine the rate of Clostridium botulinum contamination in some traditional Iranian food products (cheese, kashk and salted fish) and evaluate the efficacy of the mouse bioassay method in detection of C. botulinum toxins in these foods. A total of 131 samples (57 cheese, 11 kashk and 63 salted fish) were collected and examined to determine the rate of contamination by C. botulinum. Standard monovalent anti-toxins were used to determine the types of toxin. C. botulinum bacteria were detected in 4.58% of the examined samples (1.52% of cheese and 3.06% of salted fish samples). While no contamination was detected in the kashk samples, C. botulinum types A and E were found to be dominant in cheese and salted fish samples, respectively. These results indicate-some traditional Iranian foods may be contaminated with different types of C. botulinum, and the consumption of these products, either raw or cooked, may contribute to food-borne intoxications.

Application of slightly acidic electrolyzed water and ultrasound for microbial decontamination of kashk

“…For destruction of background microflora, 25 mL kashk samples were autoclaved insterile flasks prior to experimentation. Three different bacterial strains and one fungal strain were used for this study due to their previously reported presence in kashk (4,17). Escherichia coli O157: H7 (B0273), Bacillus cereus (ATCC 12480), Staphylococcus aureus (ATCC 25923), and Aspergillus fumigatus (ATCC 28216) were obtained from the Department of Food Science and Biotechnology, Kangwon National University, Korea.…”

“…Kashk is a low-fat dried yogurt lacking cereal additives produced in Iran that is used in or with many Iranian foods (4). It is produced both traditionally and industrially in both liquid and dried forms (Fig.…”

“…Kashk has nutritional properties of high calcium, phosphorous, and protein contents, with some fat and carbohydrates, and a pleasing taste and aroma that make it a product of consumer preference. There have been reports on kashk, especially, traditional kashk, as a source of microbial contamination (1,4). Therefore, improvement in kashk hygiene for the production process is of great importance for public health.…”

Foodborne Botulism: A Study of 57 Cases in Northwest Iran

“…Bacterial growth is inhibited by refrigeration below 4 °C, heating above 121 °C, acidity (pH <4.5) or high water activity [2]. On the other hand, toxin production may occur in special conditions that include an anaerobic milieu, low-acidity (pH of >4.6), low-salt and sugar contents, no preservatives, and a proper temperature (4 °C-120 °C) [2,8,9]. Toxin is destroyed by heating to 85 °C for at least 5 min while spores are inactivated by pressure heating to 121 °C for at least 20 min [10].…”

A review of the presence of some food contaminants on the territory of the Republic of Serbia

“…The most common bacteria involved in food contamination are Salmonella spp., Campylobacter spp., Listeria monocytogenes, Escherichia coli, Staphylococcus aureus, Clostridium botulinum, Clostridium perfrigens, and Bacillus cereus [4][5][6][7].…”